[PATCH v2 0/7] pmdomain/cpuidle-psci: Support s2idle/s2ram on PREEMPT_RT

Ulf Hansson ulf.hansson at linaro.org
Mon May 27 07:25:50 PDT 2024


Updates in v2:
	- Rebased and fixed a small issue in genpd, see patch3.
	- Re-tested on v6.9-rt5 (PREEMPT_RT enabled)
	- Re-tested on v6.10-rc1 (for regressions, PREEMPT_RT disabled)

The hierarchical PM domain topology and the corresponding domain-idle-states
are currently disabled on a PREEMPT_RT based configuration. The main reason is
because spinlocks are turned into sleepable locks on PREEMPT_RT, which means
genpd and runtime PM can't be use in the atomic idle-path when
selecting/entering an idle-state.

For s2idle/s2ram this is an unnecessary limitation that this series intends to
address. Note that, the support for cpuhotplug is left to future improvements.
More information about this are available in the commit messages.

I have tested this on a Dragonboard 410c.

Kind regards
Ulf Hansson


Ulf Hansson (7):
  pmdomain: core: Enable s2idle for CPU PM domains on PREEMPT_RT
  pmdomain: core: Don't hold the genpd-lock when calling
    dev_pm_domain_set()
  pmdomain: core: Use dev_name() instead of kobject_get_path() in
    debugfs
  cpuidle: psci-domain: Enable system-wide suspend on PREEMPT_RT
  cpuidle: psci: Drop redundant assignment of CPUIDLE_FLAG_RCU_IDLE
  cpuidle: psci: Enable the hierarchical topology for s2ram on
    PREEMPT_RT
  cpuidle: psci: Enable the hierarchical topology for s2idle on
    PREEMPT_RT

 drivers/cpuidle/cpuidle-psci-domain.c | 10 ++--
 drivers/cpuidle/cpuidle-psci.c        | 26 ++++++----
 drivers/pmdomain/core.c               | 75 +++++++++++++++++++--------
 include/linux/pm_domain.h             |  5 +-
 4 files changed, 80 insertions(+), 36 deletions(-)

-- 
2.34.1




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